Dry cell



C. W. HAZELETT.

DRY CELL.

APPLICATION FILED MAY 9, I919.

Patented; Jan. W 1922.

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INVENTOR BAN. HAZE LETT ATTORNEY UNHTED STA llE S-PATENT @DFFHQEQ'CLARENCE W. HAZELETT, 0E LAKEWOOD, QHIO, A$SIGNOR TO-N'ATIQNAL GARBONGQMJPANZ, INQ, A. CORPORATION OF NEW YORK,

DRY CELL.

Application filed May 9,

To 62% whom it may concern."

Be it known that ll, Cinnamon W. Hazannr'r, a citizen of the UnitedStates residing at Lakewood, in the county of (duyahoga and State ofUhio, have invented a certain new and useful Improvement in Dry Cells,of which the following is a full, clear, and exact description.

This invention relates to dry cells of the so-called Leclanch typehaving a hmng between the zinc electrode and the mix surrounding thcarbon electrode.

The ordinary sizes of dry cells conslst of a zinc container electrodehaving a coat ng of flour, or farinaceous starch paste. Within thecontainer a lining is fitted adyacent the inside of the pasted zinc anda dlsk 1s fitted in the bottom. The mix of manganese peroxide and carbonmoistened with an electrolyte of zinc chloride and ammonium ch10.- rideis then tamped in around a central carbon electrode. pouring hard pitchover the mix after turning a portion of the lining down over the mlx.

As far as I am aware, the only material which has been used for thispurpose in dry cells is thick paper commonly known as pulpboard. Onaccount of its porosity, capacity for absorbing electrolyte, andinertness, this material has always been considered most satisfactoryfor dry cell linings. I have now discovered that wood veneer may besubstituted for the paper lining with decidedly improved results. Beforeusing the veneer in a dry cell it is treated with dilute alkali 'or acidsolutions to remove the resinous constituents and thus increase itsporosity and flexibility. In this condition it has been found that thewood is capable of absorbing more electrolyte than the paper previouslyused. This is a decided advantage as it reduces the amount of inertmaterial in the cell and increases the quantity of electrolyte containedin the lining which is used as a carrying medium for the electrolyte.

The exact figures for the increase in quantity of: electrolyte carriedby the wood will vary depending on the kind of wood and its treatment.The use of wood as set forth in the following description, also producesa Th cell is then sealed by Specification of Letters ratent. Patmt d1Jam y 1922 1919. Serial No. 295,991.

more uniform corrosion of the zinc electrode.

In the drawings Fig. 1 is a cross section of a standard size dry cellembodying the improvement.

1g. 2 1s a cross section of a dry cell embodylng my invention as appliedto small cells commonly known as midget cells. Flg. 3 1s cross sectionof the bobbin used in the midget cells.

lflg. l is a cross section of the wooden cylinder holding the mix ofthebobbin. Referring to Flg. l, referencecharacter 1 ndicates the zinccontainer electrode and 2 1s the layer of paste thereon. A wood disk 31s inserted in the bottom of the can and the woodveneer lming 4: is thenfitted in the can by coiling a sheet of the veneer to a diameter smallenough to fit the can. soaked with electrolyte coils readily and afterinsertion springs out sufficiently to closely (fit the can.- The mix 5is then tamped around the carbon electrode 6 to the proper height and awooden disk 7 fitted over the carbon electrode to cover the min. Intampmg a cell having a paper lining-the paper is occasionally torn bythe tamping sticks, but this difiiculty is entirely eliminated with thewood veneer lining which on account of its flexibility closely fits thecan. A layer of sand 8 and a seal of pitch 9; are then applied toproperly seal the cell in a well known manner.

In applying the invention to midget cells of small diameter, aconsiderably different construction is desirable on account of thedifiiculty of coiling wood into the small cylinders of the cans.

The usual method pursued in making thes small cells consists in formingor molding a mix consisting of manganese peroxide and carbon orgraphite, moistened with electrolyte around a carbon rod. The moldecbobbin, as it is usually called, is then removed from the mold.Considerable care must be exercised in doing this and in subsequenthandling of the bobbin, as the mix is easily loosened and knocked off.The bobbin is then wrapped in thin cheesecloth which is bound thereto bmeans of string or thread 10@ wrapped aroun the cartridge, or by meansof rubber bands. The Wrapped bobbin is The veneer then inserted in azinc can having a small amount of flour paste in the bottom. As theelectrode is pushed into the can the paste is forced up around thebobbin to fill the space between the can and bobbin. The cell is thensealed at the upper end by applying successively a pulpboard collar, alayer of sand and a pitch or other seal.

The cheese cloth is used for the purpose of retaining the mix'to preventit from reaching the zinc can, which would cause short circuits,"localaction and poor shelf life. With this construction a relatively thickpastev layer is necessary in order to secure satisfactory distribution,and the size of the cartridge must be correspondingly smaller.

The object of the invention, as it relates to the midget cells, is toeliminatethe cheesecloth wrapping and the disadvantages incident to itsuse. v

According to the invention, I use a wood cylinder 11 as a retainer forthe mix of the cell. The cylinder is preferably made from a square rodof a porous grained wood such as lynn wood, cypress, cedar or yucca,which has. been treated in acid or alkali to remove the resinousconstituents and render the wood porous. Such cylinders are readily andcheaply made on an automatic screw machine which first bores out ahollow space 12, leavinga conical depression 13 due to the point of thedrill. A solid rotating arbor is then inserted and the outside turneddown to the proper size, the method permitting a treating the wood wall1 to be made as thin as desired. The cylinder is then cut ofi beyond thedepression 13 to provide a bottom 15 and a small projecting tip'16. Onaccount of the cylindrical shape and the presence of the bottom member,the cylinders are quite strong and will withstand considerable handling.It will also be understood that the acid or alkali treatment may becarried on when the cylinders are completed if desired, instead of rodsfrom which the cylinders are made. I 4

I have found that wooden cylinders made in this manner may be-turned outwith walls as thin as two one-hundredths of an inch, and that with thisthickness the wood is impervious to the mix and sufficiently porous tocontain considerable electrolyte for conduct ing the current. The spacewithin the cell is economically utilized.

In order to fill-the cylinder with mix it will be fitted in a suitablehollow cylindrical mold 17. The electrode 18 will be held in thecylinder and the mix 19 will-then be tamped around the carbon rod. inthe usual manner. The depression 13 in the bottom of the cylinder servesas a means for properly centering the lower end of the electrode. Apaper disk 20 is then fitted over the mix. and the bobbin is removed"from the mold. On account of the mix being enclosed in the drical zinccontainer,-a mix 0 wooden cylinder, it is not necessary to handle thebobbin so carefully, as themlx. cannot be accidentally knocked oi? thecartridge. The

bobbin formed in this manner is then inserted in a zinc can 21 having aquantit of paste in the bottom. The paste is force up around thecylinder, providing a layer 22 filling the space therebetween. The cellis then completed by fitting a pulpboard collar 23 in the can over thebobbin and applying a layer of sand 24 and a pitch seal 25 over themanganese peroxide and carbon and a thin sheet of porous wood veneerlocated between the mix and the zinc electrode.

2. In dry cells, a'zinc electrode, a mix of' manganese peroxide andcarbon moistened with an electrolyte and a thin sheet of porous woodveneer deprived'of its resinous constituents located between the mix andthe zinc electrode.

. 3. In dry cells, a zinc container, a mix of manganese peroxide andcarbon in said container, a chloride electrolyte in said mix and a thinsheet of porous wood veneer deprived of its resinous constituentslocated between said mix and zinc container.

4. In dry cells, a zinc electrode, a mix of manganese peroxide andcarbon, a chloride electrolyte in said mix, a thin sheet of porous woodveneer, and a thin layer of paste between the zinc and wood veneer.

5. In dry cells, a zinc container, a mix of manganese peroxideandcarbon, moistened resinous constituents and in a. porous condit1on. 1 1

7. In dry cells of the midget type, a cylinmanganese peroxide andcarbon, an electrolyte in said mix and a seamless wood'cylinder having abottom integral therewith adaptedto retain the mix, of its resinousconstituents and in a porous condition.

;8. In cells of the midget type, a cylin drical zinc container, a carbonelectrode, a mix of manganese peroxide and carbon around said carbonelectrode, an electrolyte in said mix and a seamless wood cylinderhaving a bottom integral therewith, adapted sa-id'wood cylinder beingdeprived to retain the mix, presslon in the center electrode.

Leoenlo said bottom having e dethereof for the carbon 9, In dry cells ofthe midget t pe, a cylin- 5 drical zinc container a peroxide and carbon,

mix 0 manganese an electrolyte in said mix, a seamless wood cylinderhaving a bottom integral therewith adapted to retain the mix, said woodcylinder being deprived of its resinous constituents and in a porouscond1- 16:

tion, and a layer of paste between the wood cylinder and the zinccontainer. v

In testimony whereof I hereunto aflix my signature.

c W. HAZELETT.

